Introduction. The incidence of colorectal cancer (CRC) has no downward trend and although it has stabilized in developed countries, it continues to increase in developing countries. The increase in the number of patients requires the development of new diagnostic methods. The aim of the study: to compare the results of a study of cellular atypia, namely, the activity of alkaline phosphatase (ALP), using a traditional biochemical method and electrochemical method using original biochips. Materials and methods. The activity of alkaline phosphatase was studied in biopsies of patients with CRC (n = 8), which included a fragment of the colon mucosa and tumor tissue by electrochemical and photometric methods. Results. The median of alkaline phosphatase activity detection by electrochemical method using biochips in unchanged colon mucosa was 141.38 (107.5; 183.73) nA and was 2.52 times higher than the similar values in tumor tissue, which were 56.13 (40.5; 67) (p = 0.0008). Similar data were obtained from a photometric study of ALP activity in the hydrolysis of p-nitrophenyl phosphate. A close correlation was established between the methods, Spearman's correlation coefficient was R = 0.899. Discussion and conclusions. Tumor transformation of colon mucosa epithelium is accompanied by a statistically significant decrease of alkaline phosphatase activity, regardless of the method used to register phosphatase activity. The uniformity and reliability of the decrease in ALP activity in colorectal cancer tumor tissue, detected using different methods, as well as the close correlation between the results obtained using the classical photometric study and the electrochemical method using nanotechnological biochips, indicate the possibility of using the latter for rapid, direct and inexpensive assessment of ALP activity in colorectal carcinoma biopsies.